In order to solve the problems of the greenhouse effect and rising oil prices due to the overuse of fossil fuels, a manner for transforming biomass into energy is one means of replacing traditional fossil fuels. In the development of biomass energy, microalga biodiesel is an interesting direction of research.
At present, microalgae are mainly used industrially in high unit price products, such as food, health care, biomedical products, etc. Although there is a very large of market for using microalgae in the biofuel industry, the unit price for the product is low and thus the production costs and energy consumption are aggravated. In addition, extracting oil from microalgae to form a biofuel has to disrupt cell walls of microalgae, however, this procedure is usually quite energy consuming, and thus results in the costs increasing.
In past research, it was discovered that disrupting the cell walls of microalgae using traditional methods of mechanical force consumes about 30% of the total energy contained in the microalgae, and that becomes an obstruction for industrializing microalga biofuel. Furthermore, since chemical methods for cell wall disruption need to use chemical reagents, when cells are disrupted, chemical reagents can also damage the products in the cells, and that is unfavorable to the following retrieval and use of the products. In addition, chemical disruption of cell walls also requires additional stirring power and thus makes the costs increase.
Using the traditional mechanical technique for the disruption of cell walls to treat microalgae which are high water content biomass, is highly energy consuming and does not conform with the requirements of the biofuel industry, and chemical disruption of cell walls may easily result in damage to the products in the cells, as well as requiring additional stirring power. A novel technique for the disruption of microalga cell walls that consumes less energy and costs less is needed if microalga biomass energy is to be industrialized.